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CX2SA > SATDIG 17.07.13 18:57l 835 Lines 29648 Bytes #999 (0) @ WW
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To : SATDIG@WW
Today's Topics:
1. Re: CQ-VHF Spring Edition CO6CBF Article
(Hector Luis HLMS. Martinez Sis)
2. Help wanted on CP antenna design (Phil Karn)
3. AmsatDroid Free (David Johnson)
4. Re: Help wanted on CP antenna design (Simone)
5. Re: Help wanted on CP antenna design (Zilvinas, LY2SS)
6. Re: Help wanted on CP antenna design (Simone)
7. Re: Help wanted on CP antenna design (Zach Leffke)
8. Re: Help wanted on CP antenna design (i8cvs)
9. Re: Help wanted on CP antenna design (Simone)
10. Re: Help wanted on CP antenna design (Miguel Barreiro)
11. Registration required for Colloquium SSTL visit (M5AKA)
12. Space Track TLE Retriever 2 Error Message (Rick Walter)
13. R: Space Track TLE Retriever 2 Error Message
(Claudio Ariotti, IK1SLD)
14. Re: Space Track TLE Retriever 2 Error Message (Jim Jerzycke)
15. Re: Space Track TLE Retriever 2 Error Message (Rick Walter)
----------------------------------------------------------------------
Message: 1
Date: Tue, 16 Jul 2013 15:16:42 -0500
From: "Hector Luis HLMS. Martinez Sis" <hmartinez@xxx.xxx.xx>
To: "les@xxxxxxxxxxxx.xxxx <les@xxxxxxxxxxxx.xxx>, AMSAT Mailing List
<amsat-bb@xxxxx.xxx>
Subject: [amsat-bb] Re: CQ-VHF Spring Edition CO6CBF Article
Message-ID:
<EB7F3B0CBFC9754F84FB4EF2CA6763B388F2743C3A@xxxxxxxxxxx.xxx.xxx.xx>
Content-Type: text/plain; charset="us-ascii"
Thank you Les
Hamsat is a big passion!
73!
Hector, CO6CBF
__________________________
De: amsat-bb-bounces@xxxxx.xxx [amsat-bb-bounces@xxxxx.xxxx En nombre de Les
Rayburn [les@xxxxxxxxxxxx.xxxx
Enviado el: martes, 16 de julio de 2013 02:40 a.m.
Para: AMSAT Mailing List
Asunto: [amsat-bb] CQ-VHF Spring Edition CO6CBF Article
CQ-VHF Magazine has elected to allow a free preview of the current issue
(Spring 2013) highlighting an article by Hector, CO6CBF on operating
satellites using a homebrew setup from Cuba. You can
view the entire article at:
http://www.cq-vhf.com/vhf_highlights/2013_vhf/2013_spring_vhf/2013_spring_vhf_
working_satellites.pdf
Congratulations to Hector, who is an inspiration to all of us. And if
you're not a CQ-VHF subscriber, you really should be. It's a great
magazine, and very supportive of satellite operators.
--
--
73,
Les Rayburn, N1LF
121 Mayfair Park
Maylene, AL 35114
EM63nf
6M VUCC #1712
AMSAT #38965
Grid Bandits #222
Southeastern VHF Society
Central States VHF Society Life Member
Six Club #2484
Active on 6 Meters thru 1296, 10GHz & Light
_______________________________________________
Sent via AMSAT-BB@xxxxx.xxx. Opinions expressed are those of the author.
Not an AMSAT-NA member? Join now to support the amateur satellite program!
Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb
---
Consulte la Enciclopedia Colaborativa Cubana
http://www.ecured.cu/
------------------------------
Message: 2
Date: Tue, 16 Jul 2013 22:41:08 -0700
From: Phil Karn <karn@xxxx.xxx>
To: AMSAT BB <amsat-bb@xxxxx.xxx>
Subject: [amsat-bb] Help wanted on CP antenna design
Message-ID: <51E62E74.4060007@xxxx.xxx>
Content-Type: text/plain; charset=ISO-8859-1
I'm one of several adult mentors to a local high school ham club that's
been designing and flying balloons. We are designing a high speed 70cm
digital downlink for a future payload. One of my major concerns is
frequency selective multipath fading in the 1 MHz bandwidth I plan to
use as the balloon gets low on the horizon of the tracking station and
the receiver begins to pick up a reflection off the ground.
I think one of the simpler ways to deal with multipath is to use
circular polarization on both ends. This automatically rejects all
odd-order reflections (including the all-important 1st order reflection
off the ground) as they have the opposite circularity sense to the
direct signal and automatically be cancelled at the receiver. (CP was
tried experimentally with analog TV broadcasting back in the 1970s as a
means of reducing ghosting.)
On the ground we'll just use a regular 70cm satellite antenna, but on
the balloon I need a 70cm circularly polarized transmit antenna with a
fairly wide (hemispherical) beamwidth that can maintain its circularity
over as much of that as possible.
I'm not an antenna guy, but my understanding tells me that a quadrifilar
might be a good choice here. Any comments on this? Can anybody point me
to some typical performance figures for these antennas? Again, I'm more
interested in cross-polarization rejection than in absolute gain. I have
plenty of link margin and I'm willing to sacrifice a few dB if necessary
to get rid of those deep multipath fades.
Thanks,
Phil
------------------------------
Message: 3
Date: Wed, 17 Jul 2013 08:07:54 +0100
From: David Johnson <dave@xxxxx.xx.xx>
To: AmsatBB <amsat-bb@xxxxx.xxx>
Cc: Wouter Weggelaar <w.j.weggelaar@xxxxxxxx.xx>, Ivo Klinkert
<ivo.klinkert@xxxxxx.xx>, Lars Mehnen <mehnen@xxxxxxxxxxxxxx.xx>
Subject: [amsat-bb] AmsatDroid Free
Message-ID:
<CAHOBG6UNHkcYWnj-L=YaPUiNy7nezDS3+mqV1g-JmdJ_fBia3Q@xxxx.xxxxx.xxx>
Content-Type: text/plain; charset=ISO-8859-1
Hi,
For those of you that do not get automatic updates, the latest version
1.0.5 is now in the play store.
Bug fixes and map drawing performance improvements. I also re-introduced
the prediction calculation for the current pass.
More details of the paid version at the AMSAT-UK colloquium this weekend.
73
Dave, G4DPZ
------------------------------
Message: 4
Date: Wed, 17 Jul 2013 09:11:53 +0200
From: Simone <terrando@xxxxxxx.xx>
To: Phil Karn <karn@xxxx.xxx>
Cc: AMSAT BB <amsat-bb@xxxxx.xxx>
Subject: [amsat-bb] Re: Help wanted on CP antenna design
Message-ID:
<CAKQMVSfZ-HxSMN6XgiMbU-mZ3AgTktdPXjtnWsd7LE9onerZFA@xxxx.xxxxx.xxx>
Content-Type: text/plain; charset=ISO-8859-1
Hi Phil,
QFH is effectively circularly polarized, it is often used for GPS
receivers, since when you point it skywards the main lobe points trough the
zenith, while nulls are pointing to the horizon (where you do not have
satellites normally).
In my opinion QFH risks to be quite bulky for a balloon, since it will
occupy a cylinder 1 wavelength high (70cm in your case).
To keep it simple, I would rather go for a pair of crossed dipoles 90?
phased over a ground plane: the crossed dipoles will be fairly larges
(about half wavelength, 35cm) but light since it is made of some sort of
rigid wire. The reflector can be the bottom side of the payload, if the
latter is cubic-shaped and it's at least 35x35cm (otherwise, you can use a
metal net and fix it to the bottom of the payload.
The crossed dipoles will be 1/4 of wavelength spaced from the reflector,
that is 17.5cm in free space, but can be reduced if you insert some sort of
dielectric (like Styrofoam).
The gain will be essentially an hemisphere, if you need to reduce it on the
horizontal direction, just enlarge a bit the reflector, and bend it
slightly trough the dipoles.
Unfortunately I do not have any figures on hand for the cross-polarization
performances, but IMHO, this is the best complexity-performance compromise.
73s
Simone - IU1AFY (ex. IW1FYV)
2013/7/17 Phil Karn <karn@xxxx.xxx>
> I'm one of several adult mentors to a local high school ham club that's
> been designing and flying balloons. We are designing a high speed 70cm
> digital downlink for a future payload. One of my major concerns is
> frequency selective multipath fading in the 1 MHz bandwidth I plan to
> use as the balloon gets low on the horizon of the tracking station and
> the receiver begins to pick up a reflection off the ground.
>
> I think one of the simpler ways to deal with multipath is to use
> circular polarization on both ends. This automatically rejects all
> odd-order reflections (including the all-important 1st order reflection
> off the ground) as they have the opposite circularity sense to the
> direct signal and automatically be cancelled at the receiver. (CP was
> tried experimentally with analog TV broadcasting back in the 1970s as a
> means of reducing ghosting.)
>
> On the ground we'll just use a regular 70cm satellite antenna, but on
> the balloon I need a 70cm circularly polarized transmit antenna with a
> fairly wide (hemispherical) beamwidth that can maintain its circularity
> over as much of that as possible.
>
> I'm not an antenna guy, but my understanding tells me that a quadrifilar
> might be a good choice here. Any comments on this? Can anybody point me
> to some typical performance figures for these antennas? Again, I'm more
> interested in cross-polarization rejection than in absolute gain. I have
> plenty of link margin and I'm willing to sacrifice a few dB if necessary
> to get rid of those deep multipath fades.
>
> Thanks,
>
> Phil
>
> _______________________________________________
> Sent via AMSAT-BB@xxxxx.xxx. Opinions expressed are those of the author.
> Not an AMSAT-NA member? Join now to support the amateur satellite program!
> Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb
>
------------------------------
Message: 5
Date: Wed, 17 Jul 2013 13:32:48 +0300
From: "Zilvinas, LY2SS" <zilvinas@xxxxx.xx>
Cc: AMSAT BB <amsat-bb@xxxxx.xxx>
Subject: [amsat-bb] Re: Help wanted on CP antenna design
Message-ID: <51E672D0.9020104@xxxxx.xx>
Content-Type: text/plain; charset=UTF-8; format=flowed
On 2013.07.17 10:11, Simone wrote:
> Hi Phil,
>
> QFH is effectively circularly polarized, it is often used for GPS
> receivers, since when you point it skywards the main lobe points trough the
> zenith, while nulls are pointing to the horizon (where you do not have
> satellites normally).
>
> In my opinion QFH risks to be quite bulky for a balloon, since it will
> occupy a cylinder 1 wavelength high (70cm in your case).
>
QFH for 70cm band is 264 mm height only (and 84 mm in diameter).
73!
------------------------------
Message: 6
Date: Wed, 17 Jul 2013 14:58:17 +0200
From: Simone <terrando@xxxxxxx.xx>
To: "Zilvinas, LY2SS" <zilvinas@xxxxx.xx>
Cc: AMSAT BB <amsat-bb@xxxxx.xxx>
Subject: [amsat-bb] Re: Help wanted on CP antenna design
Message-ID:
<CAKQMVSevGcRpHhoZ2qjpNHWGZd7-Rd-0pL6OA7zYLYi8ZA6jwQ@xxxx.xxxxx.xxx>
Content-Type: text/plain; charset=ISO-8859-1
I must have screwed up with units somewhere...
Simone - IU1AFY/F4VPY
2013/7/17 Zilvinas, LY2SS <zilvinas@xxxxx.xx>
>
> On 2013.07.17 10:11, Simone wrote:
>
>> Hi Phil,
>>
>> QFH is effectively circularly polarized, it is often used for GPS
>> receivers, since when you point it skywards the main lobe points trough
>> the
>> zenith, while nulls are pointing to the horizon (where you do not have
>> satellites normally).
>>
>> In my opinion QFH risks to be quite bu>>
>>
> QFH for 70cm band is 264 mm height only (and 84 mm in diameter).
>
> 73!
>
> ______________________________**_________________
> Sent via AMSAT-BB@xxxxx.xxx. Opinions expressed are those of the author.
> Not an AMSAT-NA member? Join now to support the amateur satellite program!
> Subscription settings:
http://amsat.org/mailman/**listinfo/amsat-bb<http://amsat.org/mailman/listinfo
/amsat-bb>
>
------------------------------
Message: 7
Date: Wed, 17 Jul 2013 08:59:58 -0400
From: "Zach Leffke" <zleffke@xx.xxx>
To: "'Zilvinas, LY2SS'" <zilvinas@xxxxx.xx>
Cc: 'AMSAT BB' <amsat-bb@xxxxx.xxx>
Subject: [amsat-bb] Re: Help wanted on CP antenna design
Message-ID: <001701ce82ed$8ae2ea30$a0a8be90$@xx.xxx>
Content-Type: text/plain; charset="us-ascii"
Hi Phil,
I've flown a couple of balloons as an advisor to an undergraduate
lab here at Virginia Tech. We use CP on all of our flights, though
generally we use the standard 2m APRS freq and not 70cm. Our first two
flights we flew a crossed dipole suspended above the payload (to get it out
of the view of the down facing camera) and had excellent results. Our
second flight flew the Byonics MicroTrak 300, with only 300 mW of power and
had no problems hitting digipeaters and iGates from 100,000+ feet. The
crossed dipole was constructed out of aluminum arrow shafts (rigid, but
lightweight). In an effort to drop even more weight, we changed to a design
that uses fairly rigid wire in a "turnstiled loop" configuration, more
commonly known as an eggbeater, again with excellent results from flight.
In both cases we decided to forego installing the ground plane
mentioned in previous posts. This was primarily a design decision made to
save weight at the loss of a few dB (energy radiated up does us no good with
receivers on the ground). One design that I have wanted to try but haven't
yet had the opportunity is the crossed moxon. Essentially, it is like
taking the reflector and driven elements of a pair of yagis and crossing
them at 90 degrees. It is slightly different from the Yagis as the end of
the reflector is bent 90 degrees toward the driven and the driven ends are
bent 90 degrees towards the reflector (for impedance manipulation). L.B.
Cebik, W4RNL, wrote a very useful article in the August 2001 edition of QST
describing the construction of the crossed moxon, complete with design
dimensions for a 435.6MHz crossed moxon (google can direct you to a copy of
his article). I do not have information about the cross-pole rejection, but
some time spent with 4NEC2 antenna modelling software may give you a bit of
insight.
With the bends in the elements of the moxon it focuses the pattern a
bit more towards the horizon (over the crossed dipoles). I'm not sure about
your location, but for us in SW Virginia our balloons get whipped right
along in the jet stream and we have trouble keeping up with them during the
chase (peak lateral speed in the Jetstream for our flights was 143 MPH).
The result of this is that at no time (other than the initial release when
the balloon is under about 10,000 ft) does the balloon get much higher than
maybe 20 degrees elevation. Having energy focused more towards the horizon
and less towards zenith (both in the balloon antenna and the ground
antennas) is probably not a bad Idea in our case.
If you search callsigns KK4MOB and KK4PWM on aprs.fi you can see the path of
our flights and the insanely high speeds in the Jetstream (around 30k-40k
ft).
Hope the responses help inform your decision.
GOOD LUCK!
-Zach, KJ4QLP
-----Original Message-----
From: amsat-bb-bounces@xxxxx.xxx [mailto:amsat-bb-bounces@xxxxx.xxxx On
Behalf Of Zilvinas, LY2SS
Sent: Wednesday, July 17, 2013 6:33 AM
Cc: AMSAT BB
Subject: [amsat-bb] Re: Help wanted on CP antenna design
On 2013.07.17 10:11, Simone wrote:
> Hi Phil,
>
> QFH is effectively circularly polarized, it is often used for GPS
> receivers, since when you point it skywards the main lobe points
> trough the zenith, while nulls are pointing to the horizon (where you
> do not have satellites normally).
>
> In my opinion QFH risks to be quite bulky for a balloon, since it will
> occupy a cylinder 1 wavelength high (70cm in your case).
>
QFH for 70cm band is 264 mm height only (and 84 mm in diameter).
73!
_______________________________________________
Sent via AMSAT-BB@xxxxx.xxx. Opinions expressed are those of the author.
Not an AMSAT-NA member? Join now to support the amateur satellite program!
Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb
------------------------------
Message: 8
Date: Wed, 17 Jul 2013 15:16:38 +0200
From: "i8cvs" <domenico.i8cvs@xxx.xx>
To: "AMSAT-BB" <amsat-bb@xxxxx.xxx>, "Zilvinas, LY2SS"
<zilvinas@xxxxx.xx>, "Phil Karn" <karn@xxxx.xxx>,
<terrando@xxxxxxx.xx>
Subject: [amsat-bb] Re: Help wanted on CP antenna design
Message-ID: <000e01ce82ef$e08c2a80$0401a8c0@xxxxx>
Content-Type: text/plain; charset="iso-8859-1"
Hi Zilvinas, LY2SS
I agree completely with you because the QFH was used for
the beacon of OSCAR-7 at 2304 MHz and in addition to be
endfire radiation or bakfire radiation it do not require a
reflector.
The size of a QFH for 70 cm is very small as you quoted in
264 mm height only and 84 mm in diameter and so it is not
very big and weight not to much for a balloon particularly
because there is not a reflector in it.
I hope that you as well Phil KA9Q and Simone IU1AFY
have received my pdf file concerning the QFH written by
Walter Maxwell W2DU and another one for 435 MHz
written by my self in italian for Radio Rivista 10/1998
I suggest you to read also my article:
"Experimental investigation of Quadrifilar Helix Antennas"
published by the AMSAT Journal May/June 2004
Best 73" de
i8CVS Domenico
----- Original Message -----
From: "Zilvinas, LY2SS" <zilvinas@xxxxx.xx>
Cc: "AMSAT BB" <amsat-bb@xxxxx.xxx>
Sent: Wednesday, July 17, 2013 12:32 PM
Subject: [amsat-bb] Re: Help wanted on CP antenna design
>
> On 2013.07.17 10:11, Simone wrote:
> > Hi Phil,
> >
> > QFH is effectively circularly polarized, it is often used for GPS
> > receivers, since when you point it skywards the main lobe points trough
> > the zenith, while nulls are pointing to the horizon (where you do not
have
> > satellites normally).
> >
> > In my opinion QFH risks to be quite bulky for a balloon, since it will
> > occupy a cylinder 1 wavelength high (70cm in your case).
> >
>
> QFH for 70cm band is 264 mm height only (and 84 mm in diameter).
>
> 73!
> _______________________________________________
> Sent via AMSAT-BB@xxxxx.xxx. Opinions expressed are those of the author.
> Not an AMSAT-NA member? Join now to support the amateur satellite program!
> Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb
------------------------------
Message: 9
Date: Wed, 17 Jul 2013 15:58:25 +0200
From: Simone <terrando@xxxxxxx.xx>
To: i8cvs <domenico.i8cvs@xxx.xx>
Cc: AMSAT-BB <amsat-bb@xxxxx.xxx>, Phil Karn <karn@xxxx.xxx>,
"Zilvinas, LY2SS" <zilvinas@xxxxx.xx>
Subject: [amsat-bb] Re: Help wanted on CP antenna design
Message-ID:
<CAKQMVSc92jJ8BoGbAq4Y7sHUKSOCXSAxNr1ssPTaJVeQWUpkqA@xxxx.xxxxx.xxx>
Content-Type: text/plain; charset=ISO-8859-1
Hi Domenico,
I received and briefly went trough both articles.
Seeing the front cover scan of Radio Rivista with the orange pipe brought
back to my mind that I read that article from the magazine 17 years ago...
At the time it was too soon for me to understand anything technical on
antennas but the dimensions to build them...
Best 73
Simone - IU1AFY/F4VPY
2013/7/17 i8cvs <domenico.i8cvs@xxx.xx>
> Hi Zilvinas, LY2SS
>
> I agree completely with you because the QFH was used for
> the beacon of OSCAR-7 at 2304 MHz and in addition to be
> endfire radiation or bakfire radiation it do not require a
> reflector.
>
> The size of a QFH for 70 cm is very small as you quoted in
> 264 mm height only and 84 mm in diameter and so it is not
> very big and weight not to much for a balloon particularly
> because there is not a reflector in it.
>
> I hope that you as well Phil KA9Q and Simone IU1AFY
> have received my pdf file concerning the QFH written by
> Walter Maxwell W2DU and another one for 435 MHz
> written by my self in italian for Radio Rivista 10/1998
>
> I suggest you to read also my article:
>
> "Experimental investigation of Quadrifilar Helix Antennas"
> published by the AMSAT Journal May/June 2004
>
> Best 73" de
>
> i8CVS Domenico
>
> ----- Original Message -----
> From: "Zilvinas, LY2SS" <zilvinas@xxxxx.xx>
> Cc: "AMSAT BB" <amsat-bb@xxxxx.xxx>
> Sent: Wednesday, July 17, 2013 12:32 PM
> Subject: [amsat-bb] Re: Help wanted on CP antenna design
>
>
> >
> > On 2013.07.17 10:11, Simone wrote:
> > > Hi Phil,
> > >
> > > QFH is effectively circularly polarized, it is often used for GPS
> > > receivers, since when you point it skywards the main lobe points trough
> > > the zenith, while nulls are pointing to the horizon (where you do not
> have
> > > satellites normally).
> > >
> > > In my opinion QFH risks to be quite bulky for a balloon, since it will
> > > occupy a cylinder 1 wavelength high (70cm in your case).
> > >
> >
> > QFH for 70cm band is 264 mm height only (and 84 mm in diameter).
> >
> > 73!
> > _______________________________________________
> > Sent via AMSAT-BB@xxxxx.xxx. Opinions expressed are those of the author.
> > Not an AMSAT-NA member? Join now to support the amateur satellite
> program!
> > Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb
>
>
>
------------------------------
Message: 10
Date: Wed, 17 Jul 2013 16:32:33 +0200
From: Miguel Barreiro <miguel.barreiro.paz@xxxxx.xxx>
To: Phil Karn <karn@xxxx.xxx>
Cc: AMSAT BB <amsat-bb@xxxxx.xxx>
Subject: [amsat-bb] Re: Help wanted on CP antenna design
Message-ID:
<CAKoSLJ3Q77uVY6O-gwpZJnkvAhAXJOgfEERdpRPR0XWAcBT45g@xxxx.xxxxx.xxx>
Content-Type: text/plain; charset=ISO-8859-1
Phil,
you probably know an order of magnitude better than me, but anyway: if you
have the freedom to design the transmission mode, have a look at the
techniques used by DVB-T/DVB-H, which face similar or worse multipath
problems (transmitter is much closer to the ground): use COFDM, splitting
the bandwidth into multiple subcarriers, and them modulate each subcarrier
using QPSK or even QAM. Then you are making the symbol period much longer,
improving immunity against multipath; but at the same time your symbols are
much more complex, thus binary efficiency is not much worse than a similar
single-carrier system. At high speeds doppler becomes a problem, but it's a
matter of achieving a balance between multipath immunity and doppler
tolerance.
Miguel EA1ICZ
2013/7/17 Phil Karn <karn@xxxx.xxx>
> I'm one of several adult mentors to a local high school ham club that's
> been designing and flying balloons. We are designing a high speed 70cm
> digital downlink for a future payload. One of my major concerns is
> frequency selective multipath fading in the 1 MHz bandwidth I plan to
> use as the balloon gets low on the horizon of the tracking station and
> the receiver begins to pick up a reflection off the ground.
>
> I think one of the simpler ways to deal with multipath is to use
> circular polarization on both ends. This automatically rejects all
> odd-order reflections (including the all-important 1st order reflection
> off the ground) as they have the opposite circularity sense to the
> direct signal and automatically be cancelled at the receiver. (CP was
> tried experimentally with analog TV broadcasting back in the 1970s as a
> means of reducing ghosting.)
>
> On the ground we'll just use a regular 70cm satellite antenna, but on
> the balloon I need a 70cm circularly polarized transmit antenna with a
> fairly wide (hemispherical) beamwidth that can maintain its circularity
> over as much of that as possible.
>
> I'm not an antenna guy, but my understanding tells me that a quadrifilar
> might be a good choice here. Any comments on this? Can anybody point me
> to some typical performance figures for these antennas? Again, I'm more
> interested in cross-polarization rejection than in absolute gain. I have
> plenty of link margin and I'm willing to sacrifice a few dB if necessary
> to get rid of those deep multipath fades.
>
> Thanks,
>
> Phil
>
> _______________________________________________
> Sent via AMSAT-BB@xxxxx.xxx. Opinions expressed are those of the author.
> Not an AMSAT-NA member? Join now to support the amateur satellite program!
> Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb
>
------------------------------
Message: 11
Date: Wed, 17 Jul 2013 16:03:59 +0100 (BST)
From: M5AKA <m5aka@xxxxx.xx.xx>
To: AMSAT BB <amsat-bb@xxxxx.xxx>
Subject: [amsat-bb] Registration required for Colloquium SSTL visit
Message-ID:
<1374073439.58261.YahooMailNeo@xxxxxxxxx.xxxx.xxx.xxxxx.xxx>
Content-Type: text/plain; charset=utf-8
As part of this weekendsAMSAT-UK International Space Colloquium in
Guildford, UK there will be two opportunities to visit the satellite
facilities at
the Surrey Satellite Technology Limited (SSTL) Kepler building.
The tour will only be available to those who have registered for it in
advance. The closing date for registration is 1100 GMT Thursday. Further
details at
http://amsat-uk.org/2013/07/16/registration-needed-for-sstl-kepler-visit/
For those unable to get to the Colloquium you can watch the presentations on
Saturday and Sunday on the BATC Live Events page at
http://batc.tv/ch_live.php?ch=3 The schedule is at
http://tinyurl.com/2013ColloquiumSchedule
----
73 Trevor M5AKA
AMSAT-UK website http://amsat-uk.org/
Facebook https://www.facebook.com/pages/AMSAT-UK/208113275898396
Twitter https://twitter.com/AMSAT_UK
----
------------------------------
Message: 12
Date: Wed, 17 Jul 2013 11:15:46 -0400
From: Rick Walter <wb3csy@xxxxx.xxx>
To: "amsat-bb@xxxxx.xxxx <amsat-bb@xxxxx.xxx>
Subject: [amsat-bb] Space Track TLE Retriever 2 Error Message
Message-ID:
<CAJckjgNCkHT4DrtaT41dob+yY=3=rLYYZ3D4jg2HyRq8MJ1ehg@xxxx.xxxxx.xxx>
Content-Type: text/plain; charset=ISO-8859-1
Just tried to download new Keplerian elements with Space Track TLE
Retriever 2 provided by CelesTrack and got an error message saying I should
check credentials. Anyone else getting this message? Don't know if they are
down or if I have a problem. I have been getting the latest Keps from them
for at least 15 years.
Rick
WB3CSY
--
Sent from Rick's gmail account
------------------------------
Message: 13
Date: Wed, 17 Jul 2013 18:00:21 +0200
From: "Claudio Ariotti, IK1SLD" <claudio@xxxxxxx.xxx>
To: "'Rick Walter'" <wb3csy@xxxxx.xxx>, "'amsat-bb@xxxxx.xxxxx
<amsat-bb@xxxxx.xxx>
Subject: [amsat-bb] R: Space Track TLE Retriever 2 Error Message
Message-ID: <499A677B03204EE8849D6B8165DAFB8B@xxxxxx.xxxxx>
Content-Type: text/plain; charset="iso-8859-1"
Rick,
You need to download Space Track TLE Retriever 3 because the new API used by
Space-Track site need it.
I don't remember, but I think in these days Space-Track is changing site
after a transition period since February 2013.
During this period was possible to use version 2 or 3 of TLE Retriever.
73 Claudio IK1SLD
-----Messaggio originale-----one else getting this message? Don't know if they are down
or if I have a problem. I have been getting the latest Keps from them for at
least 15 years.
Rick
WB3CSY
--
Sent from Rick's gmail account
_______________________________________________
Sent via AMSAT-BB@xxxxx.xxx. Opinions expressed are those of the author.
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------------------------------
Message: 14
Date: Wed, 17 Jul 2013 16:09:41 +0000
From: Jim Jerzycke <kq6ea@xxxxxxx.xxx>
To: amsat-bb@xxxxx.xxx
Subject: [amsat-bb] Re: Space Track TLE Retriever 2 Error Message
Message-ID: <51E6C1C5.30501@xxxxxxx.xxx>
Content-Type: text/plain; charset=ISO-8859-1; format=flowed
On 07/17/2013 03:15 PM, Rick Walter wrote:
> Just tried to download new Keplerian elements with Space Track TLE
> Retriever 2 provided by CelesTrack and got an error message saying I should
> check credentials. Anyone else getting this message? Don't know if they are
> down or if I have a problem. I have been getting the latest Keps from them
> for at least 15 years.
>
> Rick
> WB3CSY
>
They sent the following message out a week or so ago:
Dear Space-Track User,
FINAL NOTICE: Next Tuesday, 16 July 2013, at 1100 PDT (1800 UTC), the
space-track.org <http://space-track.org> team will shut off all access
to the legacy website (https://www.space-track.org/perl/***). If you
have not already done so, please transition all scripts that
screen-scrape or download text/zip files from the legacy website to the
upgraded/new website (https://www.Space-Track.org/#/recent).
If you do not transition your scripts to use the new Application
Programming Interface (API) on the upgraded site, they will not perform
correctly after we shut down the legacy website. Please visit
https://www.space-track.org/documentation for specific API information
and https://www.space-track.org/documentation/#/howto for assistance in
transitioning your scripts. We also provide several sample queries
(https://www.space-track.org/documentation/api#sampleQueries) and a
Query Builder (https://www.space-track.org/#queryBuilder) to help build
your new scripts.
Thank you,
The Space-Track Team
Engage us on your favorite social media site:
http://space-track.tumblr.com/
http://www.facebook.com/SpaceTrack
http://www.twitter.com/SpaceTrackOrg
Google+ https://www.space-track.org/g
------------------------------
Message: 15
Date: Wed, 17 Jul 2013 12:30:20 -0400
From: Rick Walter <wb3csy@xxxxx.xxx>
To: "amsat-bb@xxxxx.xxxx <amsat-bb@xxxxx.xxx>
Subject: [amsat-bb] Re: Space Track TLE Retriever 2 Error Message
Message-ID:
<CAJckjgMqAaZBwtYVrxBySCfsYJ_Q+qN1_8OzmoHEytL4HZaYBw@xxxx.xxxxx.xxx>
Content-Type: text/plain; charset=ISO-8859-1
Thanks to all who replied. I downloaded Space Track Retriever 3 and all is
well again.
73,
Rick
On Wed, Jul 17, 2013 at 11:15 AM, Rick Walter <wb3csy@xxxxx.xxx> wrote:
> Just tried to download new Keplerian elements with Space Track TLE
> Retriever 2 provided by CelesTrack and got an error message saying I should
> check credentials. Anyone else getting this message? Don't know if they are
> down or if I have a problem. I have been getting the latest Keps from them
> for at least 15 years.
>
> Rick
> WB3CSY
>
> --
> Sent from Rick's gmail account
>
--
Sent from Rick's gmail account
------------------------------
_______________________________________________
Sent via amsat-bb@xxxxx.xxx. Opinions expressed are those of the author.
Not an AMSAT member? Join now to support the amateur satellite program!
http://amsat.org/mailman/listinfo/amsat-bb
End of AMSAT-BB Digest, Vol 8, Issue 234
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